A large proportion of statistically nonsignificant randomized controlled trials (RCTs) yielded interpretations that were inconsistent with their results, according to an analysis of 31 manuscripts covering research comparing carotid endarterectomy (CEA) to carotid artery stenting (CAS) for carotid stenosis and endovascular aneurysm repair (EVAR) to open repair for abdominal aortic aneurysms (AAAs).
That was the main finding presented by Allen Li, a medical student at the University of Ottawa, Canada, during the Canadian Society for Vascular Surgery (CSVS) 2021 annual meeting (Sept. 24–25), held virtually. Li et al probed all phase-three RCTs with nonsignificant primary outcomes comparing open repair to EVAR or CEA to CAS.
Spin was identified in nine abstracts and 13 main texts among 18 AAA articles, and seven abstracts and 10 main texts across 13 carotid stenosis studies. For both, “spin was most likely to be found in the manuscript discussion section,” the authors found, and increasing journal impact factor was associated with a statistically significant lower likelihood of grade A spin, or spin in the title or abstract conclusions. No significant association could be found with funding source, they added.